The invention resides in an anchor installation in lightweight construction panels including a central support core covered by first and second cover plates wherein the anchor comprises at least one expansion body with mounting means and at least one wedge body movably disposed in the expansion body.
Flat lightweight construction panels with support cores are often also called sandwich panels, honeycomb panels or lightweight panels. All types of panels used in furniture construction have generally cover plates consisting of thin wood chip plates, medium- or high-density fiber plates, plywood or hard fiber plates. As central cores or support cores of the sandwich plates, sheets of foamed polyurethane or polystyrol are often used. In honeycomb plates as intermediate layers or, respectively, support cores, corrugated web inserts or so-called expanded honeycombs are used. Most lightweight panels have a density of less than 500 kg/m3. If, for the intermediate layers, no fire-resistant aluminum foams or foamed glass is used, the density is generally less than 350 kg/m3. For comparison, it is noted that the density of a regular woodchip plate is about 600 to 750 kg/m3.
If armatures have to be attached to the lightweight panels for example by means of screws, it is a problem that the attachment means can be connected generally only to the relatively thin cover plates or cover layers. To resolve this problem, generally expansion anchors are used as they are disclosed for example in DE 20 2004 000 474 U1. This types of expansion anchor however have the disadvantage that they engage the top cover plate at opposite sides thereof over a large area. The rear engagement fingers displace the support core material in the area around the bore in which the anchors are accommodated whereby the cover plate is released easily from the support core material and lifted off when the anchor is subjected to pulling forces.
Another anchor which avoids this disadvantage is known from the internet brochure (September 2006) of the company Fischer Befestigungssysteme GmbH: It is offered herein under the designation SLM-N. The anchor has a tubular expansion body with a bore in part of which a wedge body is accommodated, which is frustro-conically shaped and has a slotted rear expansion body end. The wedge body has an internally thread central bore. When, for example by tightening a mounting screw disposed in the thread of the wedge body, the wedge body is pulled into the expansion body which is expanded into tight engagement with the lower part of the bore. However, this anchor could be tightly held only if the core support material would be very rigid.
It is the object of the present invention to provide an anchor for lightweight construction panels which is easy to install and can be safely and durably retained in the lightweight construction panel. It is not intended for mounting to solid panel inserts or the respective panel traverse members.